Instruction manual

PC24E/25E
Page 13
2.5.7 Testing the PC24E/25E
When installation is complete, the PC24E/25E can be tested by loading and running the
programs on the supplied demonstration disk and measuring the fixed outputs using a digital
multimeter or viewing the sine wave outputs on an oscilloscope. See section 4.
2.5.8 Calibrating the PC24E
When the output voltage range of any channel is changed by jumper selection, the calibration
should be checked using the following procedure.
1. UniPolar Calibration
1.1 Ensure that the settings of jumpers J1, J2, J4 and J5 are correct for unipolar (UP)
operation on the required channels and the desired voltage range, 2.5 or 10V, is set on J3.
This voltage range applies to all four channels whether unipolar or bipolar.
1.2 Connect an accurate digital voltmeter to measure the voltage at the output of the first
channel being calibrated.
1.3 Load and run the demonstration program PC24E/25E as described in section 4.
1.4 Select item 3 from the menu. ' Write a value to all four DACs'.
1.5 Enter the data value 4095 which gives a positive full scale output voltage of +2.500 or
+10.000 as selected by J3. Press any key twice to load the DACs.
1.6 Adjust the appropriate trimmer potentiometer to give exactly +2.500V or +10.000V
according to the setting of J3. The potentiometers located at the top of the board are adjusted
according to the following table.
Channel
(DAC) Nº
Output
Pin Nº
Trimmer
Pot.
111RV1
29RV2
37RV7
45RV8
1.7 If any channel will not adjust to the required value over the full span of the
potentiometer, then raise or lower the reference voltage by adjusting RV13 until all channels
can be correctly set up. Repeat the calibration procedure.
1.8 Enter 0 and confirm to exit the program
2. BiPolar Calibration
2.1 Ensure that the settings of jumpers J1, J2, J4 and J5 are correct for bipolar (BP)
operation on the required channels and the desired voltage range, 2.5 or 10V, is set
on J3. This voltage range applies to all four channels whether unipolar or bipolar.
2.2 Connect an accurate digital voltmeter to measure the voltage at the output of the first
channel being calibrated.
2.3 Load and run the demonstration program PC24E/25E as described in section 4.
2.4 Select item 3 from the menu. ' Write a value to all four DACs'.